Pencil-sharpening machine



Aug. 5 19124. Lw

' MjBERND-r PEIWIL SHARPENING MACHINE Filed A112. 9, 1923 2 Sheets-Sheetl LSMM 9 Aug. 5 192% M. BERNDT PENCIL SHARPENING MACHINE Filed Anz. 9,1923 2 Sheets-Sheet revolution of they Patented Aug. 5, 1924.

MARTIN Bnnnnr, on nnrnr'rzscn,

P A I' E N I NEAR LEIPZIG, GERBANY, ASSIGNOR TO THE FIRM 1,504,612 FFEQ,

F INDUSTRIE-DIENST-EIN- UNI) AUSFITHE GESELLSCHAFT MIT BESCHRNKTERHAFTUNG, QF LEIPZIG, SAXQN', GERFIANY.

PENCIL-SHABPENING MACHINE.

Application filed August 9, 1923, v Serial No. 656,474.

T0 all whom z'z may concern.' Be it known that I, MARTIN BERNDT, acitizen of the German Republic, residing at Eutritzsch near Leipzig,Germany, have invented certain new and useful Improvements inPencil-Sharpening Machines, of which the following is a specification.

My invention relates to a pencil sharpening machine and moreparticularly to a machine of the kind in which a cutter-disk is providedon a manuallyoperatable shaft for cutting and sharpening the pencilwhich is firmly clamped and supported in a chuck adapted to rotatesynchronously with the manually driven cutterdisk.

In this type of pencil sharpening machines the feed of the cutter-diskis brought about by means of a hand-lever acting to press the saidcutter-disk laterally Vand obliquely against the point of the rotatingpencil, so that the operator can readily take care to not cut oftl morethan required for obtain-V ing a good point. Nevertheless it may happenthat by carelessness excessive cutting and shortening of the penciloccurs.

The main object of my invention is to provide means for preventingpanyexcessive feed of the cutter-disk and to thereby avoid loss of usefulmaterial. Viewing this object, however, it must be taken inconsideration that the chuck carrying the pencil preferably is mountedin an adjustable manner, that is to say, so as to be adapted to bodily Fturn in a horizontal plane for the adjustation purpose, whereby thepencil point will be brought to the proper angular position with respectto the cutter-disk. Forpencils of different thickness requiredifferentlyradjusted positions with relation to the cutterdisk. Hencefrom the movability ofV the chuck certain diiiiculties arise which haveto be taken into account at the realization of the problem to be solved.

`With the above object in view I connect with the chuck or the carrierthereof, proper-y ly speaking, an abutment member or stop projectingfrom the chuck or its carrier to normally lie in a horizontal planecoinciding with the horizontal plane of the axis `of the shaft of thecuttendisk, and Igive the face or edge of said abutment memberor stopopposite to the shaft of the cutter-disk a contour or shape which willprevent the cutter-disk, no matter how the chuck has been adjusted, fromunduly or excessively advancingtowards the pencil point, that is to say,cutting off from the pencil more material than required for obtaining asharp point.

Since the shapel of the conical point to be cut depends upon theadjustation or angular position to which the chuck has been set withrespect to the shaft carrying the cutter-disk, the said edge or face ofthe abutment member or stop must be shaped to form a camlthe curve ofwhich is found by practical experience. Various other objects andadvantages will become apparent during the continuance of the followingdescription.

Having thus set forth the principles upon which my invention depends andhaving shown the particular improvements effected over the prior art, Ishall now particularly describe by way of example va simple embodimentthereof which I have shown in the accompanying drawings for the purposeof more fully disclosing my invention.

In the drawing:

Figure l is a perspective view of the ma chine,

Figure 2 represents a vertical section on the line 2 2 of Fig. 3.

lFigure 3 which represents a horizontal section on the line 3-3 ofFigure 2,

Figure 4 is a similar section with the chucA set in operative position,

Figure 5 represents a vertical section on the line E F of Figure 2 andFigures 6, 7, 8 and 9 illustrate single parts of the machine, partly insection and partly on an enlarged scale.

Similar reference characters refer to similar parts in each of theseveral views.

The frame of the machine forming at the same time a kind of a casing lis shaped to form a flat platform 2 having an elongated opening or slot3 for a screw-bolt 5 with a Vfiat head or collar t to pass therethroughin order to be screwed into the bottom of the carrier 6 supporting thechuck 7. The lower end or head of the bolt 5 is suitably connected withthe means employed for mov ing the bolt in the slot 3 in order to Vturnthe chuck about a pivot pin as required for setting or adjusting thesame with relation to the cutter-disk in accordance with the thicknessof the penci-l tobe sharpened and the particular conical shape to begiven to the point thereof.

At the one side face of the carrier 6 the abutment member or stop 8 forthe lengthwise displaceable shaft of the cutter-disk is pivotallymounted on a pivot in the shape of a screw 9, as shown. The Vsaid memberor stop 3 consists of an angle-iron the vertical shank 10 of which isattached to ithe carrier 6 by mea-ns of the screw 9 whilst itshorizontal shank is 'elongated to 1project beyond the axial line VZofthe shaft of the cutter-disk. The shank 10 of the member or stop 8 isslotted as at 11 -to afforda seat for a Vpin in the shape of a screvv13, as shown in Figure 3, iixed in the carrier'. As will be Vseen fromFigures 1 vvan'd the elongated shank of the member or lstop 8 is'in thepath 14C of the cutter-disk when-the slot v11 engages the pin `or 'screw13, but if the member or stop 8 is turned about-its pivot 9 and theelongated shank is'thereby moved upwards and out yof its horizontalposition,the abutment member or stop 8 will be in an inactiverelationship with respect to the shaft 14.

The inner edge 12 of the elongated shank of the member or stop 8 issuitably curved, as will be seen from Figure 3,'to answer its purposeand extends in Figure 3, in con- I formity with Figure 1, in thehorizontal plane in which the axis-of the shaft 14"'of thel cutter-diskis situated. The'member or stop 8 may be turned upwards `and therebyremoved from its horizontal'position, shown in Figure 1, in case that'the 'pencil-:lead is wantebd to be 4totally freed 'from its 'woodenhousing, or in case that the pencil-lead, vas frequently voccurs inpencilsof inferior value, is not centrally or axially-encased in itswooden housing, so thatthe vsharpening if not counter-acted, wouldresult in an oblique non-conical lead fpoint. In acase vlike this thecutter-disk is :to be :forced towards the pencil, by means of the handIlever 58, to adopt a position Aa little `only off the median line 2-2in Figure 3- which y'could not be done, if the member Vor stop '8 werein its horizontal or stopping position, as will be readily lunderstoodfrom Figure 4l. A

further advance as far as or beyondthe median line 2-2 is 'not to begiven the cutter-disk except yin case of replacing -a worn-off disk byanew one.

The spring `16 loosely Scoiled labout Athe lshaft 14.engages with itsVone end ahub T17 integral with Ythe .pinion 1--8 keyed to thesha-ft'li, whilst the other end of the spring abuts against abushin,9;o'rfsle'eve--19 mounted in a slotted' opening A2O -of vthe Lcasing :"1,and affording a bearing for the sha-ft :14. said Vbushing orsleeve 19is rprovided'with a kind of a handle Y21 to .facilitate its Einsertion-in the opening '20, and the ,hub VM17 .is

worn off. Y Y Y By turning 'the handle 22 a gearfor `pinion 23engagin'gwith the pinion 18 and, on the other side, withthe toothed rimor edge 2a ofithechuck,is caused to rotate and to iinpart rotary motionto both the cutter-disk 135 Eand the chuck v7 holding the `pencil 46.rEhe means lfor adj usting 'or setting'the chuck tothe desired'an'gularposition withrespect to the cuttingface of 'the cutter-disk comprisestwocams 26on a shaft-28 duly supported in bearing holes ofthe wall of thecasing and in the extension 27 of the head 4i of thescrew-bolt 5,7andprovided with a crank or handle '25, as will be clearly seen in FiguresV3 to 5. f

The value of the angle at 'which the Vaxis of the chuck is setwithrelation tothe plane of the cutter-disklfcan belread on a scale' 29provided on the platform 2,'with .the aid ofla pointer 30 firmlyattached to the rear of the-chuck :7.

The particularconstruction of the chuck is an essential featureof'my'invention. The chucks yhitherto vin use gin connection withsimilar -machines are deficient inasmuch as thej1 fail 1to ensure anaccuratelyconakial position ofthe pencil and vfurther fail to holdthepencil with sufcient rigidity, so thatthe pencil will recede at theimpact of or engagement *with the cutters or cutting` blades -and arcorrectlyV conical point lcannot always be obtained'inthe machineshitherto devised. f Y

To remedy this -defect l provide -in 'the cylindrical-casing 7 ofthechuck a sleeve 33 having annular '.ianges 31 and 32., :respectively,atits ends-and mounted to be slidable in :said-casing vin accuratelyconaria'l alinementtherewith, both in the one Vdirection through thea.gency1ofa^spring 34 coiled -aboutthe `body of the fsleeve intheotheridirectionby manually or mechanshown in Figure 6.

flanges forms an annular groove 36. The end 37 of the shell projectingfrom the flange is of conical shape and six radial slots 38 areVprovided therein. These slots 38 extend inwards as far as the flange 32and six self-centering jaws 39 oit pawl-like shape with a pivot-hole 40at the inner end and a slanting edge 41 at the other end, are insertedin said slots 38 to snugly fit therein so that the holes 4() will lie inthe groove 36, as clearly shown in Figure 6.

Y 'In order to pivotally interconnect the siX jaws 39 in their assembledposition a wire 43 is threaded through the holes 40 thereof, prior tothe insertion 4of the'jaws,

and upon inserting the single jaws successively intothe-slots 38 careris vto be takenV to at the same time,V embedjthe contiguous parts ofthe wire into the groove 36. VThe two endsof the wire which isto be cutto the proper length to form a ring, arennot firmly united in order toallow the jaws to properly yield, f

The inner end of the casing of the chuck is closed by a conical insert44 having a central opening of a size or diameter correspondingV to' thethickness or diameter of the biggest pencil that might have to besharpened in the machine. yThe inner face of the conical insert 44 issloped to coincide with the slanting" edges or faces `4l of the jaws 39when the parts are in normal or inoperative' position with the jawsfully closed and no pencil 'clamped therebetween, as

In this normal position the points of the jaws 39 meet andthe edges 42of t-he jaws lie in a conical face ready for the reception of a pencil.A threaded ring 45 with a toothed outer edge 24 is screwed upon theinner end of the casing of the chuck to hold the insert 44 in place. i

On withdrawing the sleeve 33 from the casing against the pressure of thespring 34, the jaws 39 will be disengaged from the l stationary insert44 and be free to turn about their pivot wire ring 43, so that a pencilcan be introduced into the sleeve and between the aws without anynoticable resistance of the jaws to be overcome. But as soon as thesleeve 33 is released the spring 34 will act to force the sleeve inopposite direction towards the insert 44, whereby the edges or faces 4lof thejaws come in contact with the inner conical face of the insert andthe edges 42 of the jaws will grip and clamp the pencil to firmly holdthe same in an exactly conaXial position with relation to the chuck, sothat the former can neither turn nor be displaced lengthwise in thechuck.

The sleeve 33 can be withdrawn for the insertion of a pencil immediatelyby hand, preferably, however I provide a mechanical means for thepurpose. To this aim l' provide a forked lever 49 having its fulcrum at48 in a bracket projecting from the carrier 6 of the chuck 7, andengaging with its forked arm 50 the sleeve 33 in close proximity of theflange 3l thereof, whilst,

the extremity of the depending arm 47 of the lever is shaped to form apivot 52 for the reception of the hub of an arm or bar 5l secured to thearm 47 by means of a nut 53 so as to be free to 52 in a horizontalplane. The bar 5l pro* jects between two flanges 54 of a bridge 5Gintegral with a handelever 57 and forming the inner end thereof. Thebridge 56 or lever 57 is mounted on a horizontal pin 55 fixed in theframe or casingv l and acting as a pivot for the lever 57 to turnthereabout.

It will be seen that by pressing the handlever 57 down the bridge 56will likewise move downwards (about the pivot and the movement of thebridge will be trans mitted through the bar 5l to the lever 49 whichinturn will rotate about its pivot 48 whereby the sleeve 33 will bewithdrawn or partly extracted from its casing and the aws 39 thereinwill be free for the accon modation of a pencil. Upon releasing thehand-lever 57 the spring 34 inthe casing of' the sleeve 33 will act toreturn the sleeve into its former position as far as thejaws 39 holdingthe pencil firmly clamped betplfeen them and stopped by the insert 44 aVow.

It will be understood that it is necessaryv to pivotally attach the bar51 to the depending arm of the lever 49 so as to afford the bar a freeplay between t-he two flanges 54 of the bridge 56, in order tocompensate for the various angular positions the chuck may be given. Thehand-lever 58 is pivotally mounted at 59 in the wall'of the casing l andprovided with a nose 60 engaging the pinion 18 so that by manuallyexercising a pressure on the lever the pinion and the cutter-disk willbe fed towards the pencil point.

The operation of the entire Sharpener is as follows:

The lead pencil is inserted into the chuck 7 in the direction of thearrow shown in Figures l and 6, while at the same time a pressure ismanually exercised on the lever 57, whereby the sleeve 33 and the jaws39 are withdrawn against the action of the spring 34, so that the pencilbeing pushed inwards can force the jaws out of the way by turning themabout their common pivot 43. In this way the pencil can be brought to aposition, with regard to the chuck, similar to that shown in Figure lbut with the point still unsharpened. Upon releasing the lever 57 thespring 34 acts to shift the sleeve and the parts connected therewith,forwards again, that is in the direction of turn about the pivot i 'iised by contacting with "the arrow, wherebythe jaws are immobiltheinsert 44 -and holding the pencil clamped between them, the power of thespring being sufiicient to "ensure a firm hold. j

vThe pencil thus being he'ld in a proper Yposition for engagement withthe cutterdisk l5, the lever 58 `is manually lpressed inwards whilstatthe same time the handle 22 is to be turned by hand,so that thecutterdisk will be shiftedlengthwise on the shaft 14 and come in'contact with the end of the pencil, to be 'sharpened and 'at the sametime the cutter-'disk will be driven by r-the gearing '18, 23 tocut thepencil as shown 'in' Fig. l. By increasing Yor decreasing the pressureto vbe Vexercised on ithe lever 58 the cutting operation can beacceleratedf'or retarded, respective `y. 'When the -pencil 1s vproperlysharpened, the pressure fonith'e lever v'58 and LVthe turning of thehandle '22 is stopped, whereuponthe lever 57 is manually pressed ldownagainin order to'disengage thechujclr from the pencil. VThe 'pencil'then is removed ,from the 'chuck in 1the direction opposed to, thatofthe arrow. Although I have herein shown and described only one form ofthe ldevice embodyingmy invention, it is to be understood that variouschanges and modifications may loe-made herein without departing from the.spirit of my invention and the spirit and `scope of the appendedclaims.

lVhat I-claim is :el

l. A pencil sharpening machine of the type set `forth, comprising, incombination with a casing a lengthwise movable rotatable shaft, two'bearings in said casing for .the shaft, the one bearing vvconsisting ofa )removable bushing or sleeve in a slotted opening, za cutter-diskrigidly connected with said shaft, means for imparting rotary motion tosaid lshaft and cutter-disk, a means for moving the shaft with thecutter disk lengthwise, and ,la movable abutment or yst op 'having laprojecting shank vwith a curved for -camlshaped Aoperative edge,sub

st'antia-lly/as set forth.

'-2. vThe pencil-holding chuck 7, having a "sleeve, 3E "withan annulargroove, A36, and 4a -numb'er of Vclamping jaws, 39, yieldingly securedin saidgr'oove by means of an open wire ring, 43, lsubstantially asshown, for the 'purpose specified.

B. The pencil-holding chuck .7, having -a sleeve 33 with anu'mberof-yieldi'ngly secured jaws, 39, a controlling'forked lever,

